Method and apparatus for longitudinal and rotational alignment of pipe for bending with an automatic pipe bender

ABSTRACT

Method and apparatus for longitudinal and rotational alignment of a pipe for bending with an automatic pipe bender wherein an elongate length measuring template having index marks spaced along the length thereof is arranged on a work bench aligned with the pipe bender, a plurality of indexing plates are moved along the work bench to align indexing pins extending therefrom with the index marks on the length measuring template, and a rotation disc is attached to the trailing end of a pipe to be bent. The rotation disc is aligned with successive indexing pins for longitudinal alignment of the pipe for successive bends, and the rotation disc is rotated to align bores in the peripheral rim thereof with the indexing pins for rotational alignment of the pipe for successive bends.

[54] METHOD AND APPARATUS FOR LONGITUDINAL AND ROTATIONAL AlLlGNMENT OF PIPE FOR BENDING WllTll-l AN AUTOMATlC PIPE BENDER [76] Inventor: Bernard D. Ross, 2710 Emmick Rd.,

Toledo, Ohio 43606 [22] Filed: Aug. 30, 1972 [2l] Appl. No.: 284,766

[52] U.S.'Cl. 72/32, 72/36 [512iA lnt. Cl. B2lc 51/00 [58] Field of Search 72/32, 36

[56] References Cited UNlTED STATES PATENTS 2,382,745 8/l945 Powers 72/7 3,075,568 l/1963 Bright 72/ll 3,336,776 8/1967 Zerlaut 72/14 3,339,385 9/1967 Lance 72/22 3,387,473 6/1968 Noordhoek et al.. 72/22 3,559,433 2/1971 Brown et al, 72/36 3,612.1l2 l0/l97l Slegel 72/36 [11| 3,839,889 [451 on. a, i974 Primary Examiner-C W. Lanham Assistant Examiner-M. J. Keenan Attorney, Agent, 0r Firm-Robert H. Epstein [5 7 l ABSTRACT Method and apparatus for longitudinal and rotational alignment of a pipe for bending with an automatic pipe bender wherein an elongate length measuring 4template having index marks spaced along the vlength thereof is arranged on a work bench aligned with the pipe bender, a plurality of indexing plates are moved along thework bench to align indexing pins extending therefrom with the index marks on the length measur- Uing template, and a rotation disc is attached to the l0 Claims, 3 Drawing Figures METHUD AND APPARATUS FOR LONGITUDINAL AND RUTATIUNAL ALGNMENT OF PIPE FUR BENDING WITH AN AUTUMATIC PIPE BENDER BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention pertains to automatic pipe bending and, more particularly, to a method and apparatus for longitudinally and rotationally aligning a pipe to be bent with an automatic pipe bender.

2. Discussion of the Prior Art In many industries, particularly the automotive in dustry, a great number of differently configured or bent pipes are necessary to meet all requirements; and, accordingly, establishments providing such pipes must maintain vast inventories of pipes. The problem i of maintaining large inventories of pipes is particularly acute for establishments that replace exhaust systems and mufflers on vehicles in order to permit them to service the myriad makes and models of automobiles. In order to overcome this problem, many establishments have pipe bending machines on the premises such that a supply of straight pipes may be stocked and each pipe may be bent to the configuration required for the automobile to be serviced at that time.

Many attempts have been made to automate pipe bending machines in order to decrease the element of human error in the bending of pipes and the time required to bend a pipe. In patent application Ser. No. 187,099 filed Oct. 7, 1971, an automatic pipe bender is disclosed which permits the bending of pipe with precise depths automatically, inexpensively and with great speed, and the use of this automatic pipe bender has been found to be so effective in automatically controlling depth of blend as to permit a central pipe bending shop utilizing the automatic pipe bender to supply specially bent pipes to a large number of establishments servicing automobiles by replacing exhaust systems and mufflers. In the bending of a pipe, however, there are three dimensionalv considerations; longitudinal, rotational and depth of bend; and, while the automatic pipe bender of patent application Ser. No. 187,099 is extremely effective in automatically controlling depth of bend to fabricate specially bent pipes at great speeds, longitudinal and rotational alignment still must be handled by the operator running the automatic bender. Thus, the element of human error has not been reduced as far as possible due to the requirement that the operator longitudinally and rotationally move the pipe prior to each bending operation of the pipe bender normally by utilizing a tape measure and a degree wheel, respectively.

SUMMARY OF THE INVENTIONv Accordingly, it is an object of the present invention to reduce the human element of error in longitudinally and rotationally aligning a pipe for bending with an automatic pipe bender.

Another object of the present invention is to provide a method of aligning pipe for bending with an automatic pipe bender wherein a work bench is accuratelyl set up to provide indexing means for longitudinal and rotational alignment of a pipe to be bent for each bending operation of the pipe bender' without requiring length or angular measurements. y

A further object of the present invention is to provide a length measuring template for use with a work bench for an automatic pipe bender including an upstanding flange and a plurality of indexing plates slidably mounted on the flange, the length measuring template -being an elongate strip of plastic material adapted to be mounted on the flange of the work bench and carrying a plurality of index marks spaced along its length such that the indexing plates can be slid along the flange of the work bench for alignment with the indexing marks to provide -a longitudinal index for bending a pipe with a predetermined bent configuration. l

The present invention has another object in that an elongate length measuring template is arranged along a work bench and a plurality of length indexing pins are moved along the work bench such. that the pins extend through index holes in the elongate length measuring template in order to provide longitudinal indexing means for alignment with a rotation disc attached to the end of a pipe to be bent prior to a bending operation of the pipe bender, the rotation disc having bores in the periphery thereof to receive the indexing pins and provide rotational alignment for a pipe to be bent prior to each bending operation of the pipe bender such that longitudinal and rotational indices are provided for bending a pipe with a predetermined bent configuration.

An additional object of the present invention is to provide a longitudinal and rotational indexing set for eachdifferently bent pipe to be fabricated, each index` ing set including a length measuring template made of an elongate strip of plastic with index marks spaced therealong and a rotation disc having bores in the periphery thereof with numerical indicia adjacent thereto identifying successive bends for a pipe, the bores being angularly spaced corresponding to the rotation required of a pipe about its longitudinal axis prior to bending.

The present invention is generally characterized in a method of aligning pipe for bending with an automatic pipe bender including arranging an elongate length measuring template having a plurality of spaced index marks thereon along a work bench, positioning a plurality of length indexing pins along the work bench in alignment with the index marks, attaching a rotation disc to a pipe to be bent, and aligning the rotation disc with'successive ones of the length indexing pins prior to successive bending operations of the pipe bender. The present invention is further generally characterized in alignment apparatus for use with an automatic pipe bender including a work bench having an upstanding flange extending along the length thereof and a plurality of indexing plates slidably mounted on the flange and including clamping means for clamping the index'- ing plates to the flange in stationary positions along the work bench and an indexing pin extending transversely from the indexing plates.

Generally, the present invention includes four basic components, as follows: a work bench; a plurality of indexing plates having indexing pins extending therefrom; an elongate length measuring template having index holes spaced along the length thereof; and a rotation disc for attachment to the end of a pipe to be bent. To set up the work bench for bending a pipe, an end of the length measuring template is mounted on the work bench, and the length measuring templateis arranged therealong. The -indexing plates are then moved along the work bench-until the indexing pins extend through the index holes in the length measuring template; and,

thereafter, screws carried by the indexing plates are tightened to clamp the indexing plates in a stationary manner along the work bench. The rotation disc is attached to the end of a pipe to be bent in any suitable manner; and, for the first bend, the rotation disc is aligned with an end indexing pin. After the first bend is completed, the pipe is longitudinally moved toward the pipe bender until the rotation disc is aligned with the next successive indexing pin and the pipe is then rotated until the proper bore in the periphery of the rotation disc is aligned with the indexing pin, the pipe then being moved toward the work bench such that the indexing pin is received in the bore. The rotation disc is provided with numerical indicia corresponding to successive bends such that each `bore has a number provided adjacent thereto corresponding to the bend number. ln this manner, the pipe is continually, longitudinally and rotationally aligned for successive bending operations until the bending of the pipe is completed.

Some of the advantages of the present invention over the prior art are that rotational and longitudinal alignment of a pipe to be bent can be accomplished without length or angular measurements due to the unique relationship between the length measuring template, the indexing plates, the rotation disc and the work bench, and the length measuring templates and the rotation discs are made of an inexpensive material to reduce cost, the length measuring template being desirably constructed of a flexible plastic material to facilitate use, storage and transportation.

Other objects and advantages of the present invention will become apparent from the following description of the preferred embodiment taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of alignment apparatus according to the present invention.

FIG. 2 is a section taken along line 22 of FIG. ll.

FIG. 3 is a'section taken along line 3-3 of FIG. ll i1- lustrating the rotation disc.

DESCRIPTION OF THE PREFERRED EMBODIMENT Alignment apparatus according to the present invention is illustrated in FIG. 1 as utilized with a conventional pipe bender, such as models 1700 or 2007 manufactured by Huth Manufacturing Corporation. As is conventional, the pipe bender basically includes a hydraulically operated bending ram l movable during a forward stroke toward a pair of back shoes l2 and I4 which are mounted to pivot under the force from the stroke ofthe bending arm. The pipe to be bent is received in arcuate channels formed in the head of the bending ram and the back shoes, such that the pipe may be firmly held by the back shoes during the bending operation. No further detailed description is provided relative to the structure and operation of such pipe benders since they are well known, and it will be appreciated that the alignment method and apparatus of the present invention may be utilized with any suitable pipe bender.

The alignment apparatus of the present invention in-r cludes a work guide bench 16 supported'on'legs ll8 and 20 in alignment with the arcuate channels in back shoes l2 and 14 of the pipe bender in order to support and guide a straight length of pipe P to be bent. Work bench ll6 includes an elongated horizontal base 22 secured to a vertical flange member 24 extending along the flange 24, and mounts 28 and 30 are attached to the flange 24 at either end thereof.

As best illustrated in FIGS. l and 2, a plurality of indexing plates 32 are slidably mounted on flange 24, each of the indexing plates including spaced side walls 34 and 36 defining a channel therebetween for receiving flange 24. Side wall 36 has a hole 38 therein aligned with a threaded bore 40 in side wall 34. A knob 42 has a threaded stud 44 extending therefrom, the stud 44 extending through the hole 38 in side wall 36 and the slot 26 in flange 24 and threadedly received in the bore 44 in side wall 34. Tightening of knob 42 draws side walls 34 and 36 together to clamp the flange 24 and hold the indexing plates 32 in stationary positions, and loosening of the knob 42 permits the indexing plates to be slid along the flange 24 of the work bench. An indexing pin 46 extends from side wall 34 of each indexing plate transverse to the length of the work bench, the indexing pin 46 being longitudinally spaced from the stud 44.

As best illustrated in FIG. l, a length measuring ternplate 48 is mounted on the work bench i6 by tightening screws in mounts 28 and 30. The length measuring template 48 is desirably made of a flexible plastic material, such as nylon lOl 0.25 inches thick and 1.0 inch wide, such that the length measuring template may be coiled or rolled up for storage and/or transportation and may be easily handled during mounting on the work bench. The length measuring template 48 has a plurality of index holes 50 spaced along the length thereof, the index holes 50 providing means for receiving the indexing pins 46 and having a diameter slightly larger than the diameter of indexing pins 46 to permit the indexing pins to extend therethrough.

A rotation disc 52 is attached to the end of the pipe P to be bent in any suitable manner, such as by means ofa clamp bar 54 having an externally threaded post at one end thereof for engaging a plug S6 for attachment to the trailing end of the pipe P to be bent. At its opposite end, clamp bar 54 has another externally threaded post 57, and rectangular key shoulders are formed, on diametrically opposite sides of the threaded post 57 to cooperate with a keyway' 58 defined in the rotation disc 52 as illustrated in FIG. 3. The threaded post 5'7 is adapted to threadedly engage a sleeve 60 having a dowel 62 extending therethrough to provide a tightening grip for securing the rotation disc 52 to the clamp bar 54.

Rotation disc 52 has a hub 64 with a central bore 66 therethrough and equally spaced s pider legs 68 connecting the hub 64 with a peripheral rim 70. A plurality of radially extending bores 72 and a rectangular notch 74 are formed in the peripheral rim 70, and numerical indicia 76 corresponding to successive bends to be made in a pipe are disposed adjacent each bore 72 and notch 74. The diameters of bores 72 are slightly greater than the diameters of indexing pins 46 such that the indexing pins can be received therein, and rotation discs 52 are preferably made of a plastic material to facilitate insertion of the indexing pins in the bores.

For each different configuration of pipe to be bent, a longitudinal and rotational indexing set is provided,

' each indexing set'including a length measuring template 48 having index holes 50 spaced corresponding to the longitudinal displacement between bends and a rotation disc 52 having bores 72 angularly spaced corresponding to the rotational displacement between bends. The length measuring templates 48 can be mass produced by punching holes 50 in a plurality of plastic strips simultaneously and notching or bevelling the ends of the plastic strips to be mounted furthest from the pipe bender. The rotational discs 52 can be mass produced by programming spindles of degree wheels supporting the discs with stops angularly spaced according to the angular spacing between bores utilizing the notch 74 as the first position. After the length measuring templates are produced indicia is placed thereon corresponding to the pipe to be produced thereby; and, similarly, indicia corresponding to the pipes to be produced is placed on the rotation discs along with indicia 76 identifying successive bends.

In operation, a pipe bender operator selects an index ing set for a pipe to be produced including a length measuring template and a rotation disc; The indexing set can also include a schedule of depth of bends to fa` cilitate programming of the automatic pipe bender, as describedin patent application Ser. No. 187,099, now

U.S. Pat. No.3,766,764. The square end ofthe selected dexing plates 32 are slid along flange 24 to align indexr ing pins 46 with index holes 50. With the indexing pins 46 received in the index holes 50, knobs 42 are tightened to clamp side walls 34 and 36 ofthe indexing plates to the flange 24 to hold the indexing plates in stationary positions. The length measuring template can now be removed or can remain in place during bending operations. The selected rotation disc 52 is attached to the trailing end of` pipe P by screwing the clamp bar 54 into plug 56 in the end of the pipe mounting the rotation disc 52 on threaded post 57 with keyway 58 receiving the key shoulder, and tightening sleeve 60 on threaded post 57.

For the first bend, the operator aligns notch 74 with the end indexing pin 46 and actuates the pipe bender to bend the pipe. After the first bend is completed, the operator moves the pipe longitudinally toward the pipe bender to align the rotation disc 52 with the next indexing pin 46 for longitudinal alignment, and the pipe is then rotated such that the bore marked 2 receives the indexing pin. The operator then actuates the pipe bender to execute the second bend, and following bends are successively formed in the same manner.

Thus, in accordance with the present invention, precise rotational and longitudinal alignment of a pipe for bending is greatly expedited to permit the fabrication of bent pipe at great speeds with minimum error and without length or angular measurements. ln order to further reduce positioning error, the diameters ofthe indexing pins can be varied with corresponding variance in the diameters of the bores 72 in the rotation disc such that a specific indexing pin corresponding to a specific bend will be inserted snugly only in the bore 72 for the corresponding bend.

lnasmuch as the present invention is subject to many variations, modifications and changes in detail, it is'intended that all matter described above or shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense.

What is claimed is:

il. A method of aligning pipe for bending with an automatic pipe bender comprising the steps of removably arranging a ficxible elongate length measuring template along a work bench, the length measuring template having a plurality of index marks forming indexing pin receiving means spaced along the length thereof, the spacing between each successive pair of index marks corresponding to the distance between successive bends to be made in a pipe;

positioning a plurality of length. indexing pins along the work bench such that each length indexing pin is aligned with one ofthe index marks on the length measuring template;

attaching a rotation disc to a'pipe to be bent; and

aligning the rotation disc with successive ones of the length indexing pins prior to successive bending operations of the pipe bender.

2. A method of aligning pipe for bending with an automatic pipe bender comprising the steps of removably arranging a flexible elongate length measuring template along a work bench, the length measuring template having a plurality' of index holes spaced along the length thereof corresponding to the distance between successive bends to be made in a pipe;

positioning a plurality of length indexing pins along the work bench such that each length indexing pin extends through one of the index holes in the length measuring template;

attaching a rotation disc to a pipe to be bent; and

aligning the rotation disc with successive ones of the length indexing pins prior to successive bending operations of the pipe bender.

3. The method as recited in claim 2 wherein the rotation disc has a plurality of bores in the periphery thereof` angularly spaced corresponding to the rotation required of the pipe between successive bends to be made in the pipe and said aligning step includes rotating the rotation disc such that successive length indexing pins are received in successive bores during each successive bending operation of the pipe bender.

4. The alignment apparatus as recited in claim 2 and further comprising a plurality of rotation discs each associated with one of said length measuring templates and adapted to be attached to a pipe to be bent, each of saidrotation discs having a peripheral rim with a plurality of angularly spaced bores therein, said bores being angularly spaced corresponding to the rotation required of a pipe for successive bends, and each of said rotation discs carrying numerical indicia adjacent each of said bores identifying successive bends, the diameter of said bores being slightly greater than the diameter of said indexing pins and said indexing pins being received in said bores to rotationally align the pipe to be bent for bending operations of the pipe bender.

5. The alignment apparatus as recited in claim 4 wherein said flange has an elongated slot therein, said indexing plates each have a pair of spaced side walls de fining a channel receiving said flange, and said clamp` ing means includes screw means threadedly engaging one of said side walls and extending through said slot.

6. Alignment apparatus for use with an automatic pipe bender comprising a work bench having an upstanding flange extending along the length thereof;

a plurality of indexing plates slidably mounted on said flange, each of said indexing plates including clamping means for clamping said indexing plates to said flange in stationary positions along said work bench and an indexing pin extending from each of said indexing plates transverse to the length of said work bench;

a plurality of interchangeable flexible elongate length measuring templates each having a plurality of index holes spaced along the length thereof for receiving said indexing pins; and

mounting means carried by said work bench for removably mounting one of said length measuring templates along said work bench, said indexing plates being slidable along said flange to align said indexing pins with said index holes.

7. The alignment apparatus as recited in claim 6 wherein the ends of each of said length measuring templates have different configurations to indicate the end to be mounted closest to the automatic pipe bender. l

8. For use with a work bench for an automatic pipe bender, the work bench including an upstanding flange and a plurality of indexing pins slidably mounted on the flange, a length measuring template comprising an elongate strip of plasticmaterial adapted to be removably mounted on the flange of the work bench,

bender, the work bench including an upstanding flange and a plurality of indexing plates slidably mounted on the flange, a length measuring template comprising an elongate strip of plastic material adapted to be removably mounted on the flange of the work bench, said strip of plastic material carrying a plurality of index holes spaced along the length thereof corresponding to the distance between successive bends to be made in a pipe whereby the indexing plates can be slid along the flange of the work bench for alignment with said index holes positioning of a pipe to be bent. lil. The length measuring template of claim 9 wherein the ends of said s trip of plastic material have `different configurations to indicate the end to be mounted closest to the automatic pipe bender. 

1. A method of aligning pipe for bending with an automatic pipe bender comprising the steps of removably arranging a flexible elongate length measuring template along a work bench, the length measuring template having a plurality of index marks forming indexing pin receiving means spaced along the length thereof, the spacing between each successive pair of index marks corresponding to the distance between successive bends to be made in a pipe; positioning a plurality of length indexing pins along the work bench such that each length indexing pin is aligned with one of the index marks on the length measuring template; attaching a rotation disc to a pipe to be bent; and aligning the rotation disc with successive ones of the length indexing pins prior to successive bending operations of the pipe bender.
 2. A method of aligning pipe for bending with an automatic pipe bender comprising the steps of removably arranging a flexible elongate length measuring template along a work bench, the length measuring template having a plurality of index holes spaced along the length thereof corresponding to the distance between successive bends to be made in a pipe; positioning a plurality of length indexing pins along the work bench such that each length indexing pin extends through one of the index holes in the length measuring template; attaching a rotation disc to a pipe to be bent; and aligning the rotation disc with successive ones of the length indexing pins prior to successive bending operations of the pipe bender.
 3. The method as recited in claim 2 wherein the rotation disc has a plurality of bores in the periphery thereof angularly spaced corresponding to the rotation required of the pipe between successive bends to be made in the pipe and said aligning step includes rotating the rotation disc such that successive length indexing pins are received in successive bores during each successive bending operation of the pipe bender.
 4. The alignment apparatus as recited in claim 2 and further comprising a plurality of rotation discs each associated with one of said length measuring templates and adapted to be attached to a pipe to be bent, each of said rotation discs having a peripheral rim with a plurality of angularly spaced bores therein, said bores being angularly spaced corresponding to the rotation required of a pipe for successive bends, and each of said rotation discs carrying numerical indicia adjacent each of said bores identifying successive bends, the diameter of said bores being slightly greater than the diameter of said indexing pins and said indexing pins being received in said bores to rotationally align the pipe to be bent for bending operations of the pipe bender.
 5. The alignment apparatus as recited in claim 4 wherein said flange has an elongated slot therein, said indexing plates each have a pair of spaced side walls defining a channel receiving said flange, and said clamping means includes screw means threadedly engaging one of said side walls and extending through said slot.
 6. Alignment apparatus for use with an automatic pipe bender comprising a work bench having an upstanding flange extending along the length thereof; a plurality of indexing plates slidably mounted on said flange, each of said indexing plates including clamping means for clamping said indexing plates to said flange in stationary positions along said work bench and an indexing pin extending from each of said indexing plates transverse to the length of said work bench; a plurality of interchangeable flexible elongate length measuring templates each having a plurality of index holes spaced along the length thereof for receiving said indexing pins; and mounting means carried by said work bench for removably mounting one of said length measuring templates along said work bench, said indexing plates being slidable along said flange to align said indexing pins with said index holes.
 7. The alignment apparatus as recited in claim 6 wherein the ends of each of said length measuring templates have different configurations to indicate the end to be mounted closest to the automatic pipe bender.
 8. For use with a work bench for an automatic pipe bender, the work bench including an upstanding flange and a plurality of indexing pins slidably mounted on the flange, a length measuring template comprising an elongate strip of plastic material adapted to be removably mounted on the flange of the work bench, said strip of plastic material carrying a plurality of index marks forming indexing pin receiving means spaced along the length thereof, the spacing between each successive pair of index marks corresponding to the distance between successive bends to be made in a pipe whereby the indexing pins can be slid along the flange of the work bench for alignment with said index marks to index positioning of a pipe to be bent.
 9. For use with a work bench for an automatic pipe bender, the work bench including an upstanding flange and a plurality of indexing plates slidably mounted on the flange, a length measuring template comprising an elongate strip of plastic material adapted to be removably mounted on the flange of the work bench, said strip of plastic material carrying a plurality of index holes spaced along the length thereof corresponding to the distance between successive bends to be made in a pipe whereby the indexing plates can be slid along the flange of the work bench for alignment with said index holes positioning of a pipe to be bent.
 10. The length measuring template of claim 9 wherein the ends of said strip of plastic material have different configurations to indicate the end to be mounted closest to tHe automatic pipe bender. 